1. Field of the Invention
An embodiment of the present invention relates to a print apparatus including a thermal head. Another embodiment of the present invention relates to a ribbon movement control device for positioning a transfer-material area of a ribbon film at a print start position. Another embodiment of the present invention relates to a ribbon movement control method and a program that realize a function of positioning a ribbon film with respect to a print start position by rewinding the ribbon film after detection of a cue mark.
In addition, another embodiment of the present invention relates to a ribbon film suitable for a method of positioning the ribbon film with respect to a print start position by rewinding the ribbon film after detection of a cue mark.
2. Description of the Related Art
A dye-sublimation method, a melting method, and a thermosensitive method are known as printing methods used in thermal printers.
A typical thermal printer includes a line thermal head having a plurality of heating elements (resistance elements) arranged in a print width direction. The amounts of heat generated by the heating elements can be controlled individually in accordance with grayscale levels, and a plurality of dots with different grayscale levels can be recorded on a recording sheet (recording medium). In, for example, the dye-sublimation method, the amounts of heat generated by the heating elements are individually controlled while an ink ribbon is placed between the thermal head and the recording sheet, so that grayscale information is recorded on the recording sheet.
The ink ribbon is usually wound around a feed reel and a take-up reel when the ink ribbon is used. As printing proceeds, the ink ribbon is pulled out from the feed reel and is wound around the take-up reel. The ink ribbon includes a base film on which transfer-material areas formed of dye-containing material (e.g. an ink layer), thermo-compressive material (e.g. a laminate film), etc., are arranged in a longitudinal direction of the ink ribbon.
For example, yellow ink (Y), magenta ink (M), cyan ink (C), and laminate film (L) are arranged in that order.
In addition, a cue mark is formed near the leading edge of each transfer-material area on the ink ribbon. In, for example, an ink ribbon for color printing, the cue mark is used for cueing in an operation of successively transferring different colors of ink on a recording sheet.
The cue mark is, for example, a black, bar-like pattern that extends across the base film and is optically detected by a mark detection sensor positioned downstream of the thermal head.
Normally, a distance L1 between each cue mark and the leading edge of the corresponding transfer-material area is set to be equal to a distance L2 between the mark detection sensor and the thermal head. Therefore, the leading edge of the transfer-material area reaches a position directly under the thermal head (that is, a print start position) at the time when the cue mark is detected by the mark detection sensor.
FIG. 1 shows the structure of a known ink ribbon. The ink ribbon shown in FIG. 1 is can be used for performing superimposed printing using three colors of ink and covering the printed area with a laminate film.
As shown in FIG. 1, each cue mark 1 and a transfer-material area 3 corresponding to the cue mark 1 are separated from each other by a distance L1. In addition, a margin area 5 that does not contribute to printing is disposed between the adjacent transfer-material areas 3. Each cue mark 1 is positioned at the leading edge of the corresponding margin area 5.
The distance L1 is set to be equal to a distance L2 between an attachment position of a mark detection sensor and an attachment position of a thermal head.
Japanese Unexamined Patent Application Publication No. 2002-292957 discloses an example of a known structure.